Table 1.

Studies of AKI outcomes

Study and Publication YearStudy DesignCriteriaSample SizeMortality, Stage 1 (AKIN, KDIGO), or Risk (RIFLE) (95% CI)Mortality, Stage 2 (AKIN, KDIGO), or Injury (RIFLE) (95% CI)Mortality, Stage 3 (AKIN, KDIGO), or Failure (RIFLE) (95% CI)Study PopulationEnd PointSummary of Findings
Mortality
 Ostermann and Chang (23)RetrospectiveRIFLE41,972IR 20.9%aIR 45.6% aIR 56.8%a
 Hoste et al. (25)RetrospectiveRIFLE5383IR 8.8%aIR 11.4%aIR 26.3%a
 Bagshaw et al.RetrospectiveRIFLE120,123IR 17.9%aIR 27.7%aIR 33.2%a
 Lopes et al.RetrospectiveRIFLE182IR 27.3%aIR 28.6%aIR 55.0%a
 Thakar et al. (29)RetrospectiveAKIN325,395OR 2.2 (2.17 to 2.30)bOR 6.1 (5.74 to 6.44)bOR 8.6 (8.07 to 9.15)b
 Nisula et al. (11)ProspectiveAKIN, KDIGO2901IR 29.3% (25.2 to 33.3)bIR 34.1% (27.8 to 40.3)bIR 39.0% (34.3 to 43.8)b
 Hoste et al. (27)ProspectiveKDIGO1802OR 1.7 (0.9 to 3.2)bOR 3.0 (1.4 to 6.3)bOR 6.9a (3.9 to 12.2)b
Long-term outcomes
 Coca et al. 2012 (36)Systematic review and meta-analysisRIFLE, AKIN1,455,418Hospitalized and nonhospitalized patients with and without AKICKD, kidney failure, and deathAKI associated with higher risk of incident CKD (pooled aHR 8.8; 95% CI, 3.1 to 25.5), kidney failure (pooled aHR 3.1; 95% CI, 1.9 to 5.0), and mortality (pooled aHR 2.0; 95% CI, 1.3 to 3.1) Graded association with AKI severity and risk of CKD or kidney failure
 Bansal et al. 2018 (38)RetrospectiveKDIGO150,434 matched pairsHospitalized adult veterans with and without AKIIncident heart failure within 2 yr postdischargeAKI associated with higher risk of incident heart failure (HR 1.23; 95% CI, 1.19 to 1.27)
 Go et al. 2018 (39)RetrospectiveKDIGO146,941 (31,245 with AKI)Hospitalized adults with and without AKIHeart failure, acute coronary syndromes, peripheral arterial disease, ischemic stroke events (up to 1 yr postdischarge)AKI associated with higher risk of composite outcome of hospitalization for heart failure and atherosclerotic events (aHR 1.18; 95% CI, 1.13 to 1.25) Composite outcome driven by excess risk of subsequent heart failure (aHR 1.44; 95% CI, 1.33 to 1.56) Association with subsequent atherosclerotic events was nonsignificant (aHR 1.05; 95% CI, 0.98 to 1.12)
 Abdel-Kader et al. 2018 (40)Secondary analysis of prospective cohort studyKDIGO1317Critically ill adults with respiratory failure and/or shockClinical frailty status at 3 and 12 mo postdischargeIn adjusted models, AKI stages 1, 2, and 3 associated with higher frailty scores at 3 mo (OR 1.92; 95% CI, 1.14 to 3.24; OR 2.40; 95% CI, 1.31 to 4.42; OR 4.41; 95% CI, 2.20 to 8.82, respectively) Similar association between AKI stage and frailty scores at 12 mo (OR 1.87; 95% CI, 1.11 to 3.14; OR 1.81; 95% CI, 0.94 to 3.48; OR 2.76; 95% CI, 1.34 to 5.66, respectively)
 See et al. 2019 (115)Systematic review and meta-analysisRIFLE, AKIN, KDIGO, VARC, VARC-22,017,437Hospitalized adults with and without AKINew or progressive CKD, kidney failure, deathAKI was associated with higher risk of new or progressive CKD (HR 2.67; 95% CI, 1.99 to 3.58), kidney failure (HR 4.81; 95% CI, 3.04 to 7.62), and death (HR 1.80; 95% CI, 1.61 to 2.02)
 Ikizler et al. 2021 (37)Prospective observational multicenterKDIGO1538769 with AKI (+769 non-AKI matched)Hospitalized adults with and without AKIIncident CKD, CKD progression, heart failure events, major atherosclerotic cardiovascular events, all-cause mortality Mean follow-up 4.5 yr (±1.8 yr)AKI associated with higher adjusted rates of incident CKD (aHR 3.98; 95% CI, 2.51 to 6.31), CKD progression (aHR 2.37; 95% CI, 1.28 to 4.39), heart failure events (aHR 1.68; 95% CI, 1.22 to 2.31), all-cause mortality (aHR 1.78; 95% CI, 1.24 to 2.56) Risks of heart failure events and mortality nonsignificant when accounting for degree of kidney function recovery and proteinuria at 3 mo
  • AKIN, Acute Kidney Injury Network; KDIGO, Kidney Disease Improving Global Outcomes; RIFLE, Risk, Assessment, Failure, Loss, and End Stage Renal Disease; 95% CI, 95% confidence interval; IR, incidence rate; OR, odds ratio; aHR, adjusted hazard ratio; HR, hazard ratio; VARC, Valve Academic Research Consortium; VARC-2, Valve Academic Research Consortium–2.

  • a Hospital mortality.

  • b 90-d mortality rate.